From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 75B8EC77B7D for ; Thu, 18 May 2023 12:46:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230268AbjERMq4 (ORCPT ); Thu, 18 May 2023 08:46:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36830 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229917AbjERMqx (ORCPT ); Thu, 18 May 2023 08:46:53 -0400 Received: from mx0b-0031df01.pphosted.com (mx0b-0031df01.pphosted.com [205.220.180.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5E806C9 for ; Thu, 18 May 2023 05:46:52 -0700 (PDT) Received: from pps.filterd (m0279873.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 34ICQfbU021905; Thu, 18 May 2023 12:46:40 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=message-id : date : mime-version : subject : to : cc : references : from : in-reply-to : content-type : content-transfer-encoding; s=qcppdkim1; bh=7B0Wi+x/9/t51/d3MOElUht9OWrjqjL8o0y56mjT0L0=; b=Arxzreo1KltSETP2xl7mXtDAkKYiGSErf3XT3A273itHeqtD7dnBb6jOiGoYbkmZ+hkJ lpqhD8507QmLPPR2F+fplB9mMxW596Q67dh5Wd5nP2BRADHhsUQf7wYtNFLO1P4+EERt wVGutobO95mpVmFd4x0hQd+KhC9H63ce9pMi2DH4voK1OSeBm3cAshNI/Q0KHXrnzcEF 4S0xwYb/oKbgpgVXjRlqBh+c5ZcCMPVzbTbeYNSBq/MpojCWx+UpVgjNk6AZ0A+XgIy1 hY3iCDKD9J1v+XOZ6MJQORTefzg5hc37mC0Vgtbhp1XqO4XkF+NmVYMWytRQzwctozIw Dg== Received: from nalasppmta04.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3qn8d2hapa-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 18 May 2023 12:46:40 +0000 Received: from nalasex01a.na.qualcomm.com (nalasex01a.na.qualcomm.com [10.47.209.196]) by NALASPPMTA04.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 34ICkdXF024419 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 18 May 2023 12:46:39 GMT Received: from [10.216.38.166] (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.42; Thu, 18 May 2023 05:46:29 -0700 Message-ID: Date: Thu, 18 May 2023 18:16:25 +0530 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.9.1 Subject: Re: [PATCH V7 2/2] mm: shmem: implement POSIX_FADV_[WILL|DONT]NEED for shmem Content-Language: en-US To: Hugh Dickins CC: , , , , , , , , , References: <631e42b6dffdcc4b4b24f5be715c37f78bf903db.1676378702.git.quic_charante@quicinc.com> <2d56e1dd-68b5-c99e-522f-f8dadf6ad69e@google.com> From: Charan Teja Kalla In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nalasex01a.na.qualcomm.com (10.47.209.196) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: wfrWaWblBL9eRR0HJ4EnJFi6l0XjIFcE X-Proofpoint-GUID: wfrWaWblBL9eRR0HJ4EnJFi6l0XjIFcE X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.957,Hydra:6.0.573,FMLib:17.11.170.22 definitions=2023-05-18_09,2023-05-17_02,2023-02-09_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 adultscore=0 malwarescore=0 mlxlogscore=551 bulkscore=0 phishscore=0 spamscore=0 suspectscore=0 clxscore=1015 mlxscore=0 priorityscore=1501 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2304280000 definitions=main-2305180101 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Hugh, Thanks for the time and comments on this patch. On 5/17/2023 5:02 PM, Hugh Dickins wrote: >> Sure, will include those range calculations for shmem pages too. > Oh, I forgot this issue, you would have liked me to look at V8 by now, > to see whether I agree with your resolution there. Sorry, no, I've > not been able to divert my concentration to it yet. > > And it's quite likely that I shall disagree, because I've a history of > disagreeing even with myself on such range widening/narrowing issues - > reconciling conflicting precedents is difficult :( > If you can at least help by commenting which part of the patch you disagree with, I can try hard to convince you there:) . >> Please let me know if I'm missing something where I should be counting >> these as NR_ISOLATED. > Please grep for NR_ISOLATED, to see where and how they get manipulated > already, and follow the existing examples. The case that sticks in my > mind is in mm/mempolicy.c, where the migrate_pages() syscall can build > up a gigantic quantity of transiently isolated pages: your syscall can > do the same, so should account for itself in the same way. I had a V8 posted without this into accounting. Let me make the changes to account for the NR_ISOLATED too. > > I'm not claiming that mm/vmscan.c's too_many_isolated(), and the way it > gets used by shrink_inactive_list(), is perfect: not at all. But please > follow existing convention. > > Sorry, that's all for now.